Last Friday famed molecular biologist Francois Jacob passed away. Jacob, along with Andrew Lwoff and Jacques Monod, was awarded the 1965 Nobel Prize in Medicine or Physiology for identifying messenger RNA and their work on gene regulation. This research was conducted during the golden age of molecular biology--the period from the late 1940s until the early 1960s when our understanding of genetics grew leaps and bounds. Jacob described the tight-knit community of scientists at the time in an oral history interview for Web of Stories:

"There were 15 or 20 guys, always the same ones [at scientific meetings]. Roughly there were Delbrück's guys- there was the Delbrück-Luria group, Jim [Watson] who came from it because he was Luria's student. In England there was Crick and Sydney [Brenner]. And there was us here. And that's it."

The CSHL Library & Archives holds a number of letters between Jacob, Watson, Brenner, Crick, and others, which illustrate the community and friendship which existed among many of the major scientists of the era.

The letter above is from Francois Jacob to Matthew Meselson. The two, along with Sydney Brenner, conducted a famous experiment at Caltech which showed that RNA was a copy of the information in DNA. The RNA acts as a messenger, transporting the information from the nucleus to the protein-making machinery in the cell. As the letter indicates, Watson and Francois Gros were also working on RNA at the time.For more letters and photographs related to Francois Jacob please visit our online repository.